U.S. patent number 7,291,620 [Application Number 10/563,538] was granted by the patent office on 2007-11-06 for n-alkyl phenylcarboxamide beta-secretase inhibitors for the treatment of alzheimer's disease.
This patent grant is currently assigned to Merck + Co., Inc.. Invention is credited to Craig A. Coburn, Harold G. Selnick, Shawn J. Stachel, Joseph P. Vacca.
United States Patent |
7,291,620 |
Coburn , et al. |
November 6, 2007 |
N-alkyl phenylcarboxamide beta-secretase inhibitors for the
treatment of Alzheimer's disease
Abstract
The present invention is directed to compounds which are
inhibitors of the beta-secretase enzyme and which are useful in the
treatment or prevention of diseases in which the beta-secretase
enzyme is involved, such as Alzheimer's disease. The invention is
also directed to pharmaceutical compositions comprising these
compounds and the use of these compounds and compositions in the
treatment of such diseases in which the beta-secretase enzyme is
involved.
Inventors: |
Coburn; Craig A. (Royersford,
PA), Stachel; Shawn J. (Perkasie, PA), Vacca; Joseph
P. (Telford, PA), Selnick; Harold G. (Ambler, PA) |
Assignee: |
Merck + Co., Inc. (Rahway,
NJ)
|
Family
ID: |
34062007 |
Appl.
No.: |
10/563,538 |
Filed: |
June 25, 2004 |
PCT
Filed: |
June 25, 2004 |
PCT No.: |
PCT/US2004/020234 |
371(c)(1),(2),(4) Date: |
December 19, 2005 |
PCT
Pub. No.: |
WO2005/004802 |
PCT
Pub. Date: |
January 20, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060161020 A1 |
Jul 20, 2006 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60483992 |
Jun 30, 2003 |
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Current U.S.
Class: |
514/255.01;
514/605; 544/226; 548/538; 548/550; 558/413; 564/153; 564/79;
564/99; 544/391; 514/616; 514/600; 514/423; 514/424; 514/522;
514/330 |
Current CPC
Class: |
C07C
255/57 (20130101); C07C 237/10 (20130101); C07D
295/084 (20130101); A61P 25/28 (20180101); C07D
207/06 (20130101); C07C 311/08 (20130101); C07D
207/10 (20130101); C07D 207/14 (20130101); C07D
207/08 (20130101); C07D 211/38 (20130101); A61P
43/00 (20180101); C07D 295/185 (20130101); C07C
2601/02 (20170501) |
Current International
Class: |
A61K
31/4965 (20060101); A61K 31/16 (20060101); A61K
31/40 (20060101); A61K 31/445 (20060101) |
Field of
Search: |
;514/255.01,330,423,424,522,600,605,616 ;544/391,226 ;548/538,550
;558/413 ;564/79,99,153 |
References Cited
[Referenced By]
U.S. Patent Documents
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6962934 |
November 2005 |
Warpehoski et al. |
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Foreign Patent Documents
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WO89/04833 |
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Jun 1989 |
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WO |
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WO 01/00665 |
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Jan 2001 |
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WO |
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WO 02/02506 |
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Jan 2002 |
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WO |
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WO 03/043975 |
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May 2003 |
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WO |
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WO 03/057721 |
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Jul 2003 |
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WO |
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WO 2004/043916 |
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May 2004 |
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WO |
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Other References
C A. Coburn et al., "Identification of a Small Molecule Nonpeptide
Active Site Beta-Secretase Inhibitor That Displays a Nontraditional
Binding Mode for Aspartyl Proteases," J. Med. Chemistry, vol. 47,
pp. 6117-6119 (2004). cited by other.
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Primary Examiner: O'Sullivan; Peter
Attorney, Agent or Firm: Krovatin; William Todaro; John
C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. .sctn.119(e) from
Provisional Application No. 60/483,992, filed Jun. 30, 2003.
Claims
What is claimed is:
1. A compound of the formula I: ##STR00064## wherein: R.sup.1 is
selected from the group consisting of: (1) C.sub.1-6alkyl,
unsubstituted or substituted with --OR.sup.5 or
--S(O).sub.2--C.sub.1-6alkyl, (2) hydrogen, (3) phenyl, and (4)
benzyl; R.sup.2 is selected from the group consisting of: (1)
R.sup.4--S(O).sub.p--, wherein R.sup.4 is independently selected
from the group consisting of: (a) --C.sub.1-6alkyl, which is
unsubstituted or substituted with 1-6 fluoro, (b) phenyl, and (c)
benzyl, (2) R.sup.4--S(O).sub.pN(R.sup.5)--, wherein R.sup.5 is
independently selected from the group consisting of: (a) hydrogen,
(b) --C.sub.1-6alkyl, which is unsubstituted or substituted with
1-6 fluoro, (c) --C.sub.3-6cycloalkyl which is unsubstituted or
substituted with methyl, (d) phenyl, which is unsubstitued or
substituted with halo or methoxy, and (e) benzyl, (3) --CN, (4)
--C.sub.1-6alkyl-CN, (5) halogen, (6) ##STR00065## wherein R.sup.8a
and R.sup.8b are independently selected from the group consisting
of: (a) hydrogen, (b) --CN, (c) halo, (d) --C.sub.1-6alkyl, (e)
--O--R.sup.5, (f) --S--R.sup.5, (g) --CO.sub.2R.sup.5, and (h)
tetrazolyl, (7) ##STR00066## wherein n is 1, 2, 3 or 4; R.sup.3 is
selected from the group consisting of: ##STR00067## R.sup.6a,
R.sup.6b, and R.sup.6c are independently selected from the group
consisting of: (1)hydrogen, (2)halogen, (3) --OR.sup.5, (4)
--SR.sup.5, and (5) --C.sub.1-6alkyl; R.sup.7 is selected from the
group consisting of a bond, --CH=CH--, --O--, --S--, and --NH--;
R.sup.9 and R.sup.10are independently selected from the group
consisting of: (1) hydrogen, (2) C.sub.1-6alkyl, unsubstituted or
substituted with --CN or 1-4 halo, (3) --C.sub.3-6cycloalkyl, (4)
phenyl, which is unsubstitued or substituted with halo or methoxy,
and (5) benzyl, or R.sup.9 and R.sup.10 may be joined together to
form a pyrrolidine or piperidine ring which is unsubstituted or
substituted with benzyl, --OR.sup.5 or 1-4 halo; m is independently
0, 1, or 2; p is independently 0, 1, or 2, and pharmaceutically
acceptable salts thereof.
2. The compound of claim 1 wherein R.sup.1 is C.sub.1-6alkyl.
3. The compound of claim 1 wherein R.sup.1 is methyl.
4. The compound of claim 1 wherein R.sup.1 is ethyl.
5. The compound of claim 1 wherein R.sup.2 is:
R.sup.4--S(O).sub.2--NR.sup.5-- and wherein R.sup.4 is selected
from the group consisting of: (1) C.sub.1-6alkyl, (2) phenyl, and
(3) benzyl; R.sup.5 is selected from the group consisting of: (1)
C.sub.1-6alkyl, (2) phenyl, (3) benzyl, and (4) hydrogen.
6. The compound of claim 1 wherein R.sup.3 is: ##STR00068## and
wherein R.sup.5 is methyl, R.sup.6a is H or F, R.sup.6b and
R.sup.6c are hydrogen.
7. The compound of claim 1 wherein R.sup.3 is: ##STR00069##
8. The compound of claim 1 wherein R.sup.9 is hydrogen.
9. The compound of claim 1 wherein R.sup.10 is C.sub.1-6alkyl.
10. The compound of claim 1 wherein R.sup.10 is iso-butyl.
11. A compound which is selected from the group consisting of:
TABLE-US-00002 ##STR00070## ##STR00071## ##STR00072## ##STR00073##
##STR00074## ##STR00075## ##STR00076## ##STR00077## ##STR00078##
##STR00079## ##STR00080## ##STR00081## ##STR00082## ##STR00083##
##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088##
##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093##
##STR00094## ##STR00095## ##STR00096## ##STR00097## ##STR00098##
##STR00099## ##STR00100## ##STR00101## ##STR00102## ##STR00103##
##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108##
##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113##
##STR00114## ##STR00115##
and pharmaceutically acceptable salts thereof.
12. A pharmaceutical composition comprising a therapeutically
effective amount of the compound of claim 1 and a pharmaceutically
acceptable carrier.
Description
BACKGROUND OF THE INVENTION
Alzheimer's disease is characterized by the abnormal deposition of
amyloid in the brain in the form of extra-cellular plaques and
intra-cellular neurofibrillary tangles. The rate of amyloid
accumulation is a combination of the rates of formation,
aggregation and egress from the brain. It is generally accepted
that the main constituent of amyloid plaques is the 4 kD amyloid
protein (.beta.A4, also referred to as A.beta., .beta.-protein and
.beta.AP) which is a proteolytic product of a precursor protein of
much larger size. The amyloid precursor protein (APP or A.beta.PP)
has a receptor-like structure with a large ectodomain, a membrane
spanning region and a short cytoplasmic tail. The A.beta. domain
encompasses parts of both extra-cellular and transmembrane domains
of APP, thus its release implies the existence of two distinct
proteolytic events to generate its NH.sub.2-- and COOH-termini. At
least two secretory mechanisms exist which release APP from the
membrane and generate soluble, COOH-truncated forms of APP
(APP.sub.S). Proteases that release APP and its fragments from the
membrane are termed "secretases." Most APP.sub.S is released by a
putative .alpha.-secretase which cleaves within the A.beta. protein
to release .alpha.-APP.sub.S and precludes the release of intact
A.beta.. A minor portion of APP.sub.S is released by a
.beta.-secretase, which cleaves near the NH.sub.2-terminus of
A.beta. and produces COOH-terminal fragments (CTFs) which contain
the whole A.beta. domain.
Thus, the activity of .beta.-secretase, or .beta.-site amyloid
precursor protein-cleaving enzyme ("BACE"), leads to the abnormal
cleavage of APP, production A.beta., and accumulation of .beta.
amyloid plaques in the brain, which is a characteristic of
Alzheimer's disease (see R. N. Rosenberg, Arch. Neurol., vol. 59,
September 2002, pp. 1367-1368; H. Fukumoto et al, Arch. Neurol.,
vol. 59, September 2002, pp. 1381-1389; J. T. Huse et al, J. Biol.
Chem., vol 277, No. 18, issue of May 3, 2002, pp. 16278-16284; K.
C. Chen and W. J. Howe, Biochem. Biophys. Res. Comm, vol. 292, pp
702-708, 2002). Therefore, therapeutic agents that can inhibit
.beta.-secretase or BACE may be useful for the treatment of
Alzheimer's disease.
The compounds of the present invention are useful for treating
Alzheimer's disease by inhibiting the activity of the
.beta.-secretase or BACE, thus preventing the formation of
insoluble A.beta. and arresting the production of A.beta..
SUMMARY OF THE INVENTION
The present invention is directed to compounds that are inhibitors
of the .beta.-secretase enzyme and BACE and which are useful in the
treatment of diseases in which the .beta.-secretase enzyme is
involved, such as Alzheimer's disease. The invention is also
directed to pharmaceutical compositions comprising these compounds
and the use of these compounds and compositions in the prevention
or treatment of such diseases in which the .beta.-secretase enzyme
is involved.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed to compounds of the formula
I:
##STR00001## wherein: R.sup.1 is selected from the group consisting
of: (1) C.sub.1-6alkyl, unsubstituted or substituted with
--OR.sup.5 or --S(O).sub.2--C.sub.1-6alkyl, (2) hydrogen, (3)
phenyl, and (4) benzyl; R.sup.2 is selected from the group
consisting of: (1) hydrogen, (2) R.sup.4--S(O).sub.p--, wherein
R.sup.4 is independently selected from the group consisting of: (a)
C.sub.1-6alkyl, which is unsubstituted or substituted with 1-6
fluoro, (b) phenyl, and (c) benzyl, (3)
R.sup.4--S(O).sub.pN(R.sup.5)--, wherein R.sup.5 is independently
selected from the group consisting of: (a) hydrogen, (b)
--C.sub.1-6alkyl, which is unsubstituted or substituted with 1-6
fluoro, (c) --C.sub.3-6cycloalkyl which is unsubstituted or
substituted with methyl, (d) phenyl, which is unsubstitued or
substituted with halo or methoxy, and (e) benzyl, (4) --CN, (5)
--C.sub.1-6alkyl-CN, (6) halogen, (7)
##STR00002## wherein R.sup.8a and R.sup.8b are independently
selected from the group consisting of: (a) hydrogen, (b) --CN, (c)
halo, (d) --C.sub.1-6alkyl, (e) --O--R.sup.5, (f) --S--R.sup.5, (g)
--CO.sub.2R.sup.5, and (h) tetrazolyl, (8)
##STR00003## wherein n is 1, 2, 3 or 4; R.sup.3 is selected from
the group consisting of:
##STR00004## R.sup.6a, R.sup.6b, and R.sup.6c are independently
selected from the group consisting of: (1) hydrogen, (2) halogen,
(3) --OR.sup.5, (4) --SR.sup.5, and (5) --C.sub.1-6alkyl; R.sup.7
is selected from the group consisting of a bond, --CH.dbd.CH--,
--O--, --S--, and --NH--; R.sup.9 and R.sup.10 are independently
selected from the group consisting of: (1) hydrogen, (2)
C.sub.1-6alkyl, unsubstituted or substituted with --CN or 1-4 halo,
(3) --C.sub.3-6cycloalkyl, (4) phenyl, which is unsubstitued or
substituted with halo or methoxy, and (5) benzyl, or R.sup.9 and
R.sup.10 may be joined together to form a pyrrolidine or piperidine
ring which is unsubstituted or substituted with benzyl, --OR.sup.5
or 1-4 halo; m is independently 0, 1, or 2; p is independently 0,
1, or 2, and pharmaceutically acceptable salts thereof.
An embodiment of the present invention includes compounds wherein
R.sup.1 is C.sub.1-6alkyl.
Another embodiment of the present invention includes compounds
wherein R.sup.1 is methyl.
Another embodiment of the present invention includes compounds
wherein R.sup.1 is ethyl.
Another embodiment of the present invention includes compounds
wherein R.sup.2 is: R.sup.4--S(O).sub.2--NR.sup.5-- and wherein
R.sup.4 is selected from the group consisting of: (1)
C.sub.1-6alkyl, (2) phenyl, and (3) benzyl; R.sup.5 is selected
from the group consisting of: (1) C.sub.1-6alkyl, (2) phenyl, (3)
benzyl, and (4) hydrogen.
Another embodiment of the present invention includes compounds
wherein R.sup.3 is:
##STR00005## and wherein R.sup.5 is methyl, R.sup.6a is H or F,
R.sup.6b and R.sup.6c are hydrogen.
Another embodiment of the present invention includes compounds
wherein R.sup.3 is:
##STR00006##
Another embodiment of the present invention includes compounds
wherein R.sup.9 is hydrogen.
Another embodiment of the present invention includes compounds
wherein R.sup.10 is C.sub.1-6alkyl.
Another embodiment of the present invention includes compounds
wherein R.sup.10 is iso-butyl.
Another embodiment of the present invention includes a compound
which is selected from the title compounds of the following
Examples and pharmaceutically acceptable salts thereof.
The compounds of the instant invention have at least one asymmetric
center. Additional asymmetric centers may be present depending upon
the nature of the various substituents on the molecule. Compounds
with asymetric centers give rise to enantiomers (optical isomers),
diastereomers (configurational isomers) or both, and it is intended
that all of the possible enantiomers and diastereomers in mixtures
and as pure or partially purified compounds are included within the
scope of this invention. The present invention is meant to
encompass all such isomeric forms of these compounds.
The independent syntheses of the enantiomerically or
diastereomerically enriched compounds, or their chromatographic
separations, may be achieved as known in the art by appropriate
modification of the methodology disclosed herein. Their absolute
stereochemistry may be determined by the x-ray crystallography of
crystalline products or crystalline intermediates that are
derivatized, if necessary, with a reagent containing an asymmetric
center of known absolute configuration.
If desired, racemic mixtures of the compounds may be separated so
that the individual enantiomers are isolated. The separation can be
carried out by methods well known in the art, such as the coupling
of a racemic mixture of compounds to an enantiomerically pure
compound to form a diastereomeric mixture, followed by separation
of the individual diastereomers by standard methods, such as
fractional crystallization or chromatography. The coupling reaction
is often the formation of salts using an enantiomerically pure acid
or base. The diasteromeric derivatives may then be converted to the
pure enantiomers by cleavage of the added chiral residue. The
racemic mixture of the compounds can also be separated directly by
chromatographic methods utilizing chiral stationary phases, which
methods are well known in the art.
Alternatively, any enantiomer of a compound may be obtained by
stereoselective synthesis using optically pure starting materials
or reagents of known configuration by methods well known in the
art.
The compounds of the present invention are prepared by the methods
outlined in Scheme 1.
##STR00007##
Referring to Scheme 1, N-Boc protected amino acids (1--A) are
reacted with primary or secondary amines in the presence of a
coupling agent such as BOP reagent and an amine base to afford an
N-protected amino amide (1--B). The Boc group is removed under
acidic conditions such as HCl gas in ethyl acetate. The resulting
amino acid amide salt (1--C) is reductively aminated with boc
protected phenylalanine aldehyde using a reducing agent such as
sodium cyanoborohydride in methanol. The product (1-D) is treated
with a strong acid such as HCl gas or trifluoroacetic acid to
remove the t-butyloxycarbonyl protecting group to provide the
intermediate diamine salt (1-E). Compounds 1-E are coupled to
benzoic acid derivatives by standard amide coupling procedures such
as BOP reagent and a trialkylamine base to provide final compounds
(I).
##STR00008## ##STR00009##
Scheme 2 illustrates an alternative process for the synthesis of
inhibitors (I). Boc-Phe is reduced by standard methods to afford
the corresponding alcohol (2-B). The resulting alcohol is activated
for azide displacement by treatment with methanesulfonyl chloride
and an amine base such as triethylamine. Azide formation takes
place by reacting mesylate 2-C with an excess of sodium azide in a
polar aprotic solvent such as DMF at an elevated temperature. The
product (2-D) is treated with a strong acid such as HCl gas to
remove the t-butyloxycarbonyl protecting group to provide the amino
azide salt 2-E. Standard amide coupling of amine 2-E with a benzoic
acid derivative provides 2-F. The azide functional group is reduced
with a phosphine reagent to provide 2-G which is then alkylated
with an appropriately substituted bromoacetate ester and a base
such as potassium carbonate. The ester 2-H is then saponified with
a base such as lithium hydroxide to afford the corresponding
carboxylic acid. Compounds 2-I are coupled to a benzoic acid
derivative by standard amide coupling procedures such as BOP
reagent and a trialkylamine base to provide final compounds I.
A wide variety of benzoic acids are applicable to schemes 1 and 2
and include examples where R.sup.2 is sulfonamide, sulfone, amide,
nitrile, alkylnitrile, halogen, phenyl, and cyanocycloalkyl.
R.sup.3 of the benzoic acid in Schemes 1 and 2 is generally
selected from a carboxyaminobenzyl group, a substituted olefin, an
O or N alkylcyclopropyl, or an alkyl ether, alkylthioether, or
secondary amine.
The term "substantially pure" means that the isolated material is
at least 90% pure, and preferably 95% pure, and even more
preferably 99% pure as assayed by analytical techniques known in
the art. The term "pharmaceutically acceptable salts" refers to
salts prepared from pharmaceutically acceptable non-toxic bases or
acids including inorganic or organic bases and inorganic or organic
acids. Salts derived from inorganic bases include aluminum,
ammonium, calcium, copper, ferric, ferrous, lithium, magnesium,
manganic salts, manganous, potassium, sodium, zinc, and the like.
Particularly preferred are the ammonium, calcium, magnesium,
potassium, and sodium salts. Salts in the solid form may exist in
more than one crystal structure, and may also be in the form of
hydrates. Salts derived from pharmaceutically acceptable organic
non-toxic bases include salts of primary, secondary, and tertiary
amines, substituted amines including naturally occurring
substituted amines, cyclic amines, and basic ion exchange resins,
such as arginine, betaine, caffeine, choline,
N,N'-dibenzylethylene-diamine, diethylamine, 2-diethylaminoethanol,
2-dimethylaminoethanol, ethanolamine, ethylenediamine,
N-ethyl-morpholine, N-ethylpiperidine, glucamine, glucosamine,
histidine, hydrabamine, isopropylamine, lysine, methylglucamine,
morpholine, piperazine, piperidine, polyamine resins, procaine,
purines, theobromine, triethylamine, trimethylamine,
tripropylamine, tromethamine, and the like. When the compound of
the present invention is basic, salts may be prepared from
pharmaceutically acceptable non-toxic acids, including inorganic
and organic acids. Such acids include acetic, benzenesulfonic,
benzoic, camphorsulfonic, citric, ethanesulfonic, fumaric,
gluconic, glutamic, hydrobromic, hydrochloric, isethionic, lactic,
maleic, malic, mandelic, methanesulfonic, mucic, nitric, pamoic,
pantothenic, phosphoric, succinic, sulfuric, tartaric,
p-toluenesulfonic acid, and the like. Particularly preferred are
citric, hydrobromic, hydrochloric, maleic, phosphoric, sulfuric,
fumaric, and tartaric acids.
The present invention is directed to the use of the compounds
disclosed herein as inhibitors of .beta.-secretase enzyme activity
or .beta.-site amyloid precursor protein-cleaving enzyme ("BACE")
activity, in a patient or subject such as a mammal in need of such
inhibition, comprising the administration of an effective amount of
the compound. The terms ".beta.-secretase enzyme," ".beta.-site
amyloid precursor protein-cleaving enzyme," and "BACE" are used
interchangably in this specification. In addition to humans, a
variety of other mammals can be treated according to the method of
the present invention.
The present invention is further directed to a method for the
manufacture of a medicament or a composition for inhibiting
.beta.-secretase enzyme activity in humans and animals comprising
combining a compound of the present invention with a pharmaceutical
carrier or diluent.
The compounds of the present invention have utility in treating,
preventing, ameliorating, controlling or reducing the risk of
Alzheimer's disease, other diseases mediated by abnormal cleavage
of amyloid precursor protein (also referred to as APP), and other
conditions that may be treated or prevented by inhibition of
.beta.-secretase. Such conditions include mild cognitive
impairment, Trisomy 21 (Down Syndrome), cerebral amyloid
angiopathy, degenerative dementia, Hereditary Cerebral Hemorrhage
with Amyloidosis of the Dutch-Type (HCHWA-D), Creutzfeld-Jakob
disease, prion disorders, amyotrophic lateral sclerosis,
progressive supranuclear palsy, head trauma, stroke, Down syndrome,
pancreatitis, inclusion body myositis, other peripheral
amyloidoses, diabetes and atherosclerosis.
The subject or patient to whom the compounds of the present
invention is administered is generally a human being, male or
female, in whom inhibition of .beta.-secretase enzyme activity is
desired, but may also encompass other mammals, such as dogs, cats,
mice, rats, cattle, horses, sheep, rabbits, monkeys, chimpanzees or
other apes or primates, for which inhibition of .beta.-secretase
enzyme activity or treatment of the above noted disorders is
desired.
The compounds of the present invention may be used in combination
with one or more other drugs in the treatment, prevention, control,
amelioration, or reduction of risk of diseases or conditions for
which the compounds of the present invention have utility, where
the combination of the drugs together are safer or more effective
than either drug alone. Additionally, the compounds of the present
invention may be used in combination with one or more other drugs
that treat, prevent, control, ameliorate, or reduce the risk of
side effects or toxicity of the compounds of the present invention.
Such other drugs may be administered, by a route and in an amount
commonly used therefor, contemporaneously or sequentially with the
compounds of the present invention. Accordingly, the pharmaceutical
compositions of the present invention include those that contain
one or more other active ingredients, in addition to the compounds
of the present invention. The combinations may be administered as
part of a unit dosage form combination product, or as a kit or
treatment protocol wherein one or more additional drugs are
administered in separate dosage forms as part of a treatment
regimen.
Examples of combinations of the compounds of the present invention
with other drugs in either unit dose or kit form include
combinations with: anti-Alzheimer's agents, for example other
beta-secretase inhibitors or gamma-secretase inhibitors; HMG-CoA
reductase inhibitors; NSAID's including ibuprofen; vitamin E;
anti-amyloid antibodies; CB-1 receptor antagonists or CB-1 receptor
inverse agonists; antibiotics such as doxycycline and rifampin;
N-methyl-D-aspartate (NMDA) receptor antagonists, such as
memantine; cholinesterase inhibitors such as galantamine,
rivastigmine, donepezil and tacrine; or other drugs that affect
receptors or enzymes that either increase the efficacy, safety,
convenience, or reduce unwanted side effects or toxicity of the
compounds of the present invention. The foregoing list of
combinations is illustrative only and not intended to be limiting
in any way.
The term "composition" as used herein is intended to encompass a
product comprising specified ingredients in predetermined amounts
or proportions, as well as any product which results, directly or
indirectly, from combination of the specified ingredients in the
specified amounts. This term in relation to pharmaceutical
compositions is intended to encompass a product comprising one or
more active ingredients, and an optional carrier comprising inert
ingredients, as well as any product which results, directly or
indirectly, from combination, complexation or aggregation of any
two or more of the ingredients. In general, pharmaceutical
compositions are prepared by uniformly and intimately bringing the
active ingredient into association with a liquid carrier or a
finely divided solid carrier or both, and then, if necessary,
shaping the product into the desired formulation. In the
pharmaceutical composition the active object compound is included
in an amount sufficient to produce the desired effect upon the
process or condition of diseases.
Pharmaceutical compositions intended for oral use may be prepared
according to any method known to the art for the manufacture of
pharmaceutical compositions and such compositions may contain one
or more agents selected from the group consisting of sweetening
agents, flavoring agents, coloring agents and preserving agents in
order to provide pharmaceutically elegant and palatable
preparations. Tablets contain the active ingredient in admixture
with non-toxic pharmaceutically acceptable excipients which are
suitable for the manufacture of tablets. These excipients may be
for example, inert diluents, granulating and disintegrating agents,
binding agents and lubricating agents. The tablets may be uncoated
or they may be coated by known techniques to delay disintegration
and absorption in the gastrointestinal tract and thereby provide a
sustained action over a longer period.
Compositions for oral use may also be presented as hard gelatin
capsules wherein the active ingredient is mixed with an inert solid
diluent or as soft gelatin capsules wherein the active ingredient
is mixed with water or an oil medium.
Aqueous suspensions contain the active materials in admixture with
excipients suitable for the manufacture of aqueous suspensions.
Such excipients include suspending agents and dispersing or wetting
agents. The aqueous suspensions may also contain one or more
preservatives, coloring agents, flavoring agents, and sweetening
agents.
Oily suspensions may be formulated by suspending the active
ingredient in a vegetable oil or in a mineral oil. The oily
suspensions may contain a thickening agent. Sweetening agents and
flavoring agents may be added to provide a palatable oral
preparation. These compositions may be preserved by the addition of
an anti-oxidant.
Dispersible powders and granules suitable for preparation of an
aqueous suspension by the addition of water provide the active
ingredient in admixture with a dispersing or wetting agent,
suspending agent and one or more preservatives. Additional
excipients, for example sweetening, flavoring and coloring agents,
may also be present.
The pharmaceutical compositions of the invention may also be in the
form of oil-in-water emulsions, which may also contain excipients
such as sweetening and flavoring agents.
The pharmaceutical compositions may also be in the form of a
sterile injectable aqueous or oleagenous suspension, which may be
formulated according to the known art, or may be administered in
the form of suppositories for rectal administration of the
drug.
The compounds of the present invention may also be administered by
inhalation, by way of inhalation devices known to those skilled in
the art, or transdermally by way of transdermal patch.
By "pharmaceutically acceptable" it is meant the carrier, diluent
or excipient must be compatible with the other ingredients of the
formulation and not deleterious to the recipient thereof.
The terms "administration of" or "administering a" compound should
be understood to mean providing a compound of the invention to the
individual in need of treatment in a form that can be introduced
into that individuals body in a therapeutically useful form and
therapeutically useful amount, including, but not limited to: oral
dosage forms, such as tablets, capsules, syrups, suspensions, and
the like; injectable dosage forms, such as IV, IM, or IP, and the
like; transdermal dosage forms, including creams, jellies, powders,
or patches; buccal dosage forms; inhalation powders, sprays,
suspensions, and the like; and rectal suppositories.
The terms "effective amount" or "therapeutically effective amount"
means the amount of the subject compound that will elicit the
biological or medical response of a tissue, system, animal or human
that is being sought by the researcher, veterinarian, medical
doctor or other clinician. As used herein, the term "treatment"
refers both to the treatment and to the prevention or prophylactic
therapy of the mentioned conditions, particularly in a patient who
is predisposed to such disease or disorder.
As used herein, the term "treatment" or "treating" means any
administration of a compound of the present invention and includes
(1) inhibiting the disease in an animal that is experiencing or
displaying the pathology or symptomatology of the diseased (i.e.,
arresting further development of the pathology and/or
symptomatology), or (2) ameliorating the disease in an animal that
is experiencing or displaying the pathology or symptomatology or
the diseased (i.e., reversing the pathology and/or symptomatology).
The term "controlling" includes preventing, treating, eradicating,
ameliorating or otherwise reducing the severity of the condition
being controlled.
The compositions containing compounds of the present invention may
conveniently be presented in unit dosage form and may be prepared
by any of the methods well known in the art of pharmacy. The term
"unit dosage form" is taken to mean a single dose wherein all
active and inactive ingredients are combined in a suitable system,
such that the patient or person adminstering the drug to the
patient can open a single container or package with the entire dose
contained therein, and does not have to mix any components together
from two or more containers or packages. Typical examples of unit
dosage forms are tablets or capsules for oral administration,
single dose vials for injection, or suppositories for rectal
administration. This list of unit dosage forms is not intended to
be limiting in any way, but merely to represent typical examples in
the pharmacy arts of unit dosage forms.
The compositions containing compounds of the present invention may
conveniently be presented as a kit, whereby two or more components,
which may be active or inactive ingredients, carriers, diluents,
and the like, are provided with instructions for preparation of the
actual dosage form by the patient or person adminstering the drug
to the patient. Such kits may be provided with all necessary
materials and ingredients contained therein, or they may contain
instructions for using or making materials or components that must
be obtained independently by the patient or person administering
the drug to the patient.
When treating, preventing, controlling, ameliorating, or reducing
the risk of Alzheimer's disease or other diseases for which
compounds of the present invention are indicated, generally
satisfactory results are obtained when the compounds of the present
invention are administered at a daily dosage of from about 0.1
milligram to about 100 milligram per kilogram of animal body
weight, preferably given as a single daily dose or in divided doses
two to six times a day, or in sustained release form. The total
daily dosage is from about 1.0 milligrams to about 2000 milligrams,
preferably from about 0.1 milligrams to about 20 milligrams per
kilogram of body weight. In the case of a 70 kg adult human, the
total daily dose will generally be from about 7 milligrams to about
1,400 milligrams. This dosage regimen may be adjusted to provide
the optimal therapeutic response. The compounds may be administered
on a regimen of 1 to 4 times per day, preferably once or twice per
day.
Specific dosages of the compounds of the present invention, or
pharmaceutically acceptable salts thereof, for administration
include 1 mg, 5 mg, 10 mg, 30 mg, 80 mg, 100 mg, 150 mg, 300 mg and
500 mg. Pharmaceutical compositions of the present invention may be
provided in a formulation comprising about 0.5 mg to 1000 mg active
ingredient, more preferably comprising about 0.5 mg to 500 mg
active ingredient or 0.5 mg to 250 mg active ingredient, or 1 mg to
100 mg active ingredient.
It will be understood, however, that the specific dose level and
frequency of dosage for any particular patient may be varied and
will depend upon a variety of factors including the activity of the
specific compound employed, the metabolic stability and length of
action of that compound, the age, body weight, general health, sex,
diet, mode and time of administration, rate of excretion, drug
combination, the severity of the particular condition, and the host
undergoing therapy.
The utility of the compounds in accordance with the present
invention as inhibitors of .beta.-secretase enzyme activity may be
demonstrated by methodology known in the art. Enzyme inhibition is
determined as follows.
FRET Assay: A homogeneous end point fluorescence resonance energy
transfer (FRET) assay is employed with the substrate
([TAMRA-5-CO-EEISEVNLDAEF-NHQSY]QFRET), which is cleaved by BACE 1
to release the fluorescence from TAMRA. The Km of the substrate is
not determined due to the limit of solubility of the substrate. A
typical reaction contains approximately 30 nM enzyme, 1.25 .mu.M of
the substrate, and buffer (50 mM NaOAc, pH 4.5, 0.1 mg/ml BSA, 0.2%
CHAPS, 15 mM EDTA and 1 mM deferoxamine) in a total reaction volume
of 100 .mu.l. The reaction is proceeded for 30 min and the
liberation of TAMRA fragment is measured in a 96-well plate LJL
Analyst AD using an excitation wavelength of 530 nm and an emission
wavelength of 580 nm. Under these conditions, less than 10% of
substrate is processed by BACE 1. The enzyme used in these studies
was soluble (transmembrane domain and cytoplasmic extension
excluded) human protein produced in a baculovirus expression
system. To measure the inhibitory potency of compounds, solutions
of inhibitor in DMSO (four concentrations of the inhibitors were
prepared: 1 mM, 100 .mu.M, 10 .mu.M, 1 .mu.M) were included in the
reactions mixture (final DMSO concentration is 0.8%). All
experiments were conducted at room temperature using the standard
reaction conditions described above. To determine the IC.sub.50 of
the compound, competitive equation V0/Vi=1+[I]/[IC50] was used to
predict the inhibitory potency of the compounds. The errors in
reproducing the dissociation constants are typically less than
two-fold.
HPLC assay: A homogeneous end point HPLC assay is employed with the
substrate (coumarin-CO-REVNFEVEFR), which is cleaved by BACE 1 to
release the N-terminal fragment attached with coumarin. The Km of
the substrate is greater than 100 .mu.M and can not be determined
due to the limit of solubility of the substrate. A typical reaction
contains approximately 2 nM enzyme, 1.0 .mu.M of the substrate, and
buffer (50 mM NaOAc, pH 4.5, 0.1 mg/ml BSA, 0.2% CHAPS, 15 mM EDTA
and 1 mM deferoxamine) in a total reaction volume of 100 .mu.l. The
reaction is proceeded for 30 min and the reaction is stopped by the
addition of 25 .mu.L of 1 M Tris-HCl, pH 8.0. The resulting
reaction mixture was loaded on the HPLC and the product was
separated from substrate with 5 min linear gradient. Under these
conditions, less than 10% of substrate is processed by BACE 1. The
enzyme used in these studies was soluble (transmembrane domain and
cytoplasmic extension excluded) human protein produced in a
baculovirus expression system. To measure the inhibitory potency
for compounds, solutions of inhibitor in DMSO (12 concentrations of
the inhibitors were prepared and the concentration rage was
dependent on the potency predicted by FRET) were included in the
reaction mixture (final DMSO concentration is 10%). All experiments
were conducted at room temperature using the standard reaction
conditions described above. To determine the IC.sub.50 of the
compound, four parameters equation is employed for curve fitting.
The errors in reproducing the dissociation constants are typically
less than two-fold.
In particular, the compounds of the following examples had activity
in inhibiting the beta-secretase enzyme in the aforementioned
assay, generally with an IC.sub.50 from about 1 nM to 1 .mu.M. Such
a result is indicative of the intrinsic activity of the compounds
in use as inhibitors the beta-secretase enzyme activity.
Several methods for preparing the compounds of this invention are
illustrated in the following Schemes and Examples. Starting
materials are made according to procedures known in the art or as
illustrated herein. The following examples are provided so that the
invention might be more fully understood. These examples are
illustrative only and should not be construed as limiting the
invention in any way.
Intermediate I
##STR00010##
Step A: To a solution containing 2.0 g (10.0 mmol) of
(S)--N-Boc-aminobutyric acid in 50 mL of DCM was added 730 mg (10.0
mmol) of isobutyl amine, 4.42 g (10.0 mmol) of BOP Reagent and 4.2
mL (24.0 mmol) of Hunig's base. The reaction mixture was stirred at
rt for 30 min before it was extracted with 10% citric acid (10 mL),
water (10 mL), saturated NaHCO.sub.3 (10 mL) and brine (10 mL). The
organic phase was dried over MgSO.sub.4, concentrated and
chromatographed (1:1 EtOAc/Hexanes) to afford 2.4 g of the desired
amide. .sup.1H NMR .delta. 6.11 (bs, 1H), 4.96 (bs, 1H), 3.97 (m,
1H), 3.08 (m, 2H), 1.88 (m, 1H), 1.80 (m, 1H), 1.66 (m, 1H), 1.45
(s, 9H), 0.95 (m, 9H). LCMS (M+H)=259.27
Step B: A 0.degree. C. solution containing 1.58 g (6.10 mmol) of
Boc amide A was dissolved in 40 mL of EtOAc and 4 ml of MeOH and
saturated with HCl gas for 10 minutes. The reaction mixture was
stirred for 1 h then concentrated to a semi-solid. The residue was
triturated with 50 mL of ether to afford 1.10 g of the amine HCl
salt as an extremely hygroscopic solid. .sup.1H NMR (CD.sup.3OD)
.delta. 3.78 (t, J=7.8 Hz, 1H), 3.18 (m, 2H), 1.85 (m, 3H), 1.01
(t, J=7.8 Hz, 3H), 0.87 (d, 6H). LCMS (M+H)=159.31
Step C: To a solution containing 200 mg (0.76 mmol) of
(S)--N-Boc-Phe-CHO in 5 mL of MeOH was added 746 mg (3.81 mmol, 5
equiv) of amine B and 47.0 mg (0.76 mmol) of NaBH.sub.3CN. The
resulting solution was stirred at rt over 16 h. The solvent was
removed and the residue was dissolved in 25 mL of DCM and washed
with NaHCO.sub.3 (10 mL) and brine (10 mL). Evaporation of the
solvent and chromatography (EtOAc) left 245 mg of the desired
product that was used directly in the next reaction. .sup.1H NMR
(CDCl.sub.3) .delta. 7.4-7.1 (m, 5H), 4.84 (d, J=2.4 Hz, 1H), 4.11
(bs, 1H), 3.60 (bs, 1H), 3.11 (m, 4H), 2.82 (m, 4H), 1.81 (m, 4H),
1.43 (s, 9H), 0.99 (t, J=7.8 Hz, 3H), 0.82 (d, J=7.7 Hz, 6H).
Step D: A 0.degree. C. solution containing 201 mg (0.5 mmol) of Boc
amine from step C was dissolved in 25 mL of EtOAc and saturated
with HCl gas for 5 minutes. The reaction mixture was stirred for 1
h, concentrated and triturated with ether to afford 185 mg of
compound I as a white solid. .sup.1H NMR (CD3OD) .delta. 7.44-7.15
(m, 5H), 3.83 (m, 1H), 3.33 (m, 1H), 3.18 (m, 1H), 3.06 (m, 4H),
2.00 (m, 2H), 1.77 (m, 1H), 1.01 (t, J=7.8 Hz, 3H), 0.88 (d, J=7.8
Hz, 6H).
Intermediate II
##STR00011##
Prepared similar to Intermediate I but substituting
(S)--N-Boc-aminopentanoic acid as the amine in step A. .sup.1H NMR
(CD.sub.3OD) .delta. 8.55 (bt, 1H), 7.41-7.26 (m, 5H), 3.92 (t,
J=6.8 Hz, 2H), 3.77 (dd, 2H), 3.30 (d, J=1.7 Hz, 1H), 3.08 (dd,
J=13.5, 1.7 Hz, 1H), 3.03-2.95 (m, 4H), 1.88 (m, 2H), 1.77 (m, 1H),
1.41 (m, 2H), 0.94 (t, J=7.4 Hz, 3H), 0.90 (d, J=6.8 Hz, 6H)
Intermediate III
##STR00012##
Prepared similar to Intermediate I but substituting
(S)--N-Boc-methionine sulfone as the amine in step A. .sup.1H NMR
(CD.sub.3OD) .delta. 8.42 (bs, 1H), 7.44-7.25 (m, 5H), 4.02 (m,
1H), 3.83 (m, 1H), 3.38-3.05 (m, 7H), 3.00 (s, 3H), 2.39 (bd, 2H),
1.77 (m, 1H), 0.92 (d, J=6.7 Hz, 6H).
##STR00013##
Intermediate IV
Prepared similar to Intermediate I but substituting
(S)--N-Boc-alanine as the amine in step A. .sup.1H NMR (CD.sub.3OD)
.delta. 8.41 (bt, 1H), 7.41-7.26 (m, 5H), 4.02 (m, 1H), 3.81 (m,
2H), 3.40-3.00 (m, 5H), 1.80 (m, 2H), 1.61 (d, J=6.7 Hz, 3H), 0.97
(d, J=6.8 Hz, 6H)
Intermediate V
##STR00014##
Prepared similar to Intermediate I but substituting
(S)--N-Boc-homoserine as the amine in step A. .sup.1H NMR
(CD.sub.3OD):. .delta. 7.37-7.27 (m, 5H), 4.13 (m, 1H), 3.99 (m,
1H), 3.86-3.75 (m, 2H), 3.38-3.25 (m, 2H), 3.03 (m, 2H), 2.89 (m
1H), 2.76 (d, J=7.14 Hz, 2H), 2.14 (m, 1H), 1.99 (m, 1H), 1.01 (d,
J=6.68 Hz, 6H). LCMS (M+H)=308.1
EXAMPLE 1
##STR00015##
Step A. To a stirred slurry of dimethyl 5-aminoisophthalate (5.0 g,
23.90 mmol) in 100 mL CH.sub.2Cl.sub.2/Pyridine (3:1) at 0.degree.
C. was added methanesulfonyl chloride (1.85 mL, 23.90 mmol). The
resulting mixture was stirred for 4 h at room temperature. The
solvent was removed in vacuo and ethyl acetate (100 mL) was added
resulting in precipitate formation. The product was collected by
filtration to give 5.14 g of the sulfonamide as a white solid.
.sup.1H NMR (DMSO.sub.d6) .delta. 8.15 (s, 1H), 8.02 (s, 2H), 3.89
(s, 6H), 3.02 (s, 3H). LCMS [M-OCH.sub.3].sup.+=256.16
Step B. To a solution of sodium hydride (0153 g, 3.83 mmol, 60% oil
dispersion) in 10 mL DMF was added sulfonamide (1.0 g, 3.48 mmol)
from step A followed by methyl iodide (0.43 mL, 6.97 mmol). After 1
hr the reaction was quenched with H.sub.2O (100 mL) and extracted
with EtOAc (3.times.50 mL). The organic extracts were dried over
MgSO.sub.4 and evaporated to give 1.03 g of N-methylsulfonamide.
.sup.1H NMR (DMSO.sub.d6) .delta. 8.40 (s, 1H), 8.19 (s, 2H), 3.91
(s, 6H), 3.34 (s, 3H), 3.01 (s, 3H). LCMS [M+H]=302.15
Step C. Diester (1.03 g, 3.38 mmol) from step B was dissolved in 50
mL THF: MeOH (1:1) and cooled to 0.degree. C. 1N NaOH (3.38 mL,
3.38 mmol) was added and the reaction was allowed to warm to RT
over 8 hours. The solution was acidified with 1N HCl (30 mL) and
extracted with EtOAc (3.times.50 mL). The combined organic extracts
were washed with brine and dried over MgSO.sub.4, filtered and
concentrated in vacuo. Purification on silica gel (5%
MeOH/CHCl.sub.3 containing 1% HOAc) gave 795 mg (82%) of the mono
acid. .sup.1H NMR (DMSO.sub.d6) .delta. 8.30 (s, 1H), 8.10 (s, 2H),
3.84 (s, 3H), 3.27 (s, 3H), 2.94 (s, 3H). LCMS (M+H)=288.16
Step D. A solution containing 133 mg (0.46 mmol) of the monoacid
from step C in 5 mL CH.sub.2Cl.sub.2, BOP reagent (0.235 g, 0.55
mmol), (R)-- (+)-4-fluoro-methylbenzylamine (76 mg, 0.55 mmol), and
diisopropylethylamine (0.24 mL, 1.39 mmol) was stirred at ambient
temperature for 1 h. Evaporation of the solvent and column
chromatography on silica gel (90% EtOAc/Hexanes) afforded 71 mg of
the benzyl amide. LCMS (M+H)=409.27
Step E. To 179 mg (0.438 mmol) of the benzyl amide from step D in
10 mL THF:MeOH (1:1) was added 2 N NaOH (0.66 mL, 1.32 mmol). The
solution was heated to 50.degree. C. for 1 h. After cooling the
solution was acidified by the addition of 1 N HCl (20 mL) and
extracted with EtOAc (3.times.30 mL). The combined organic extracts
were dried over MgSO.sub.4, filtered, and concentrated in vacuo to
yield 173 g of the desired carboxylic acid. .sup.1H NMR
(CDCl.sub.3) .delta. 8.22 (t, 1H), 8.11 (m, 1H), 8.06 (m, 1H), 7.34
(m, 5H), 6.47 (d, J=7.1 Hz, 1H), 5.33 (m, 1H), 3.37 (s, 3H), 2.87
(s, 3H), 1.64 (d, J=7.0 Hz, 3H). LCMS (M+H)=395.2
Step F. To a solution containing 39.5 mg (0.10 mmol) of the
carboxylic acid from step E in 5 mL of DCM was added intermediate
amine dihydrochloride IV (35.7 mg, 0.10 mmol), 44.2 mg (0.10 mmol)
of BOP reagent and 0.076 mL (0.44 mmol) of diisopropylethyl amine.
The reaction mixture was stirred at rt for 1 h then extracted with
2.times.1 mL 1N HCl, 2.times.1 mL water, and 1 mL brine. The
organic phase was dried over MgSO.sub.4 and subjected to reverse
phase chromatography to afford 57.7 mg of the desired product as a
white solid. 1H NMR (CD.sub.3OD) .delta. 9.03 (d, J=7.69 Hz, 1H),
8.90 (bs, 1H), 8.61 (d, J=8.42 Hz, 1H), 8.45 (m, 1H), 8.23 (s, 1H),
8.03 (s, 1H), 7.92 (s, 1H), 7.44 (m, 2H), 7.29-7.14 (m, 7H), 5.19
(m, 1H), 4.51 (bs, 1H), 3.86 (m, 1H), 3.30 (s, 3H), 3.10 (bs, 1H),
3.00 (s, 3H), 2.99-2.87 (m, 4H), 1.68 (m, 1H), 1.50 (d, J=7.15 Hz,
3H), 1.40 (d, J=6.77 Hz, 3H). LCMS (M+H)=654.28.
EXAMPLE 2
##STR00016##
Step A: To 3-amino-5-nitrobenzoic acid (3.60 g, 19.78 mmol) in 100
mL MeOH was added thionyl chloride (2,59 g, 21.76 mmol). The
solution was heated to 65.degree. C. for 12 h. Concentration in
vacuo afforded the 4.57 g of the methyl ester hydrochloride salt.
.sup.1H NMR (CD.sub.3OD) .delta. 8.62 (s, 1H), 8.28 (s, 1H), 8.19
(s, 1H), 3.99 (s, 3H).
Step B: To a solution of 3.53 g (18.0 mmol) amino ester from step A
in 100 mL CH.sub.2Cl.sub.2/pyridine (3:1) was added methanesulfonyl
chloride (2.07 g, 18.0 mmol). The reaction was stirred at ambient
temperature for 1 h followed by evaporation of the solvent. The
gummy residue was taken up in EtOAc (100 mL), acidified with 1N HCl
(100 mL), and extracted with EtOAc (3.times.100 mL). The combined
organic extracts were dried over MgSO.sub.4, filtered, and
concentrated in vacuo to provide 3.97 of the sulfonamide as an
off-white solid. .sup.1H NMR (CD.sub.3OD) .delta. 8.46 (s, 1H),
8.30 (s, 1H), 8.18 (s, 1H), 3.97 (s, 3H), 3.09 (s, 3H).
Step C: Sodium Hydride (0.26 g, 6.55 mmol, 60% oil dispersion) was
suspended in 10 mL DMF to which 1.5 g (5.45 mmol) of the
sulfonamide from step B in 10 mL DMF was added followed by 0.93 g
(6.55 mL) methyl iodide. The solution was stirred at ambient
temperature for 3 h. The reaction was quenched with H.sub.2O (250
mL), extracted with EtOAc (3.times.200 mL), dried over MgSO.sub.4,
filtered and concentrated in vacuo. Purification by silica gel
chromatography provided 1.43 g of the N-methyl sulfonamide. LCMS
(M-H.sub.2O)=272.2
Step D. To a solution of the nitro sulfonamide (2.7 g, mmol) from
step C and 0.15 g of 10% Pd/C in 50 mL EtOH containing HOAc (2 mL)
was stirred at room temperature under a balloon of hydrogen gas for
12 h. The mixture was filtered through a pad of Celite,
concentrated, and purified on silica gel (100% EtOAc) to afford
2.05 g of the desired aniline. .sup.1H NMR (CD.sub.3OD) .delta.
7.29 (s, 1H), 7.26 (s, 1H), 6.95 (s, 1H), 3.87 (s, 3H), 3.27 (sm
3H), 2.89 (s, 3H). LCMS (M+H)=258.2
Step E. A solution containing 0.32 g (1.3 mmol) of the aniline from
step D, 0.33 g (2.5 mmol) of 1-bromo-2-butyne, and 0.35 g (2.5
mmol) K.sub.2CO.sub.3 in 12.5 mL of acetonitrile was heated at
reflux for 4 h The reaction mixture was cooled and diluted with 60
mL of H.sub.2O. The mixture was extracted with of EtOAc (3.times.60
mL). The combined organics were washed with brine (60 mL) then
dried (MgSO.sub.4). The solvent was removed in vacuo and purified
by silica gel chromatography (20%-50% EtOAc:Hex) to afford 160.0 mg
of alkynyl aniline. LCMS (M+H)=311.2
Step F. A solution containing 83 mg (0.27 mmol) of alkynyl aniline
from step E in 3 mL MeOH was treated with a catalytic amount of
Lindlar's catalyst and stirred at room temperature under a hydrogen
atmosphere for 10 min. The reaction was filtered through plug of
silica gel and the solvent was removed in vacuo. Purification by
reverse phase HPLC afforded 38 mg of Z-alkenyl aniline. LCMS
(M+H)=313.2
Step G. A solution containing 38 mg (0.12 mmol) Z-alkenyl aniline
from step F in 2.5 mL EtOAc at 0.degree. C. was treated with 58 mg
(1.3 mmol) of freshly prepared diazomethane and a catalytic amount
of palladium acetate and stirred at 0.degree. C. for 15 min. The
reaction was filtered through a plug of silica gel. Evaporation of
the solvent left 34.0 mg of the methyl cyclopropyl methyl aniline.
LCMS (M+H)=327.2
Step H. To 34 mg (0.10 mmol) of the methyl cyclopropyl methyl
aniline from step G in 5 mL THF:MeOH (1:1) was added 2 N NaOH (0.15
mL, 0.30 mmol). The solution was heated to 50.degree. C. for 1 h.
After cooling the solution was acidified by the addition of 1 N HCl
(20 mL) and extracted with EtOAc (3.times.30 mL). The combined
organic extracts were dried over MgSO.sub.4, filtered, and
concentrated in vacuo to yield 0.020 g of the desired carboxylic
acid. LCMS (M+H)=313.2
Step I. A solution containing 31.3 mg (0.10 mmol) of the carboxylic
acid from step H, 37.6 mg (0.1 mmol) of intermediate diamine II,
44.4 mg (0.1 mmol) of BOP reagent and 0.076 mL (0.44 mmol) of
Hunig's base were stirred at rt for 1 h in 5 mL of DCM. The solvent
was evaporated and the residue was purified by reverse phase
chromatography to afford 35 mg of the title compound as a white
solid. .sup.1H NMR (CD.sub.3OD) .delta. 7.32-6.98 (m, 8H), 4.59 (m,
1H), 4.14-4.07 (m, 1H), 3.84 (m 1H), 3.36 (s, 3H), 3.33 (m, 2H),
3.31 (s, 3H), 3.24-3.07 (m, 2H), 3.01 (m, 2H), 2.92 (m, 3H), 2.03
(m, 2H), 1.87-1.63 (m, 4H), 1.25 (m, 1H), 1.07 (m, 2H), 0.97 (m,
3H), 0.92 (d, J=6.6 Hz, 6H), 0.83-0.76 (m, 1H). LCMS
(M+H)=600.32
EXAMPLE 3
##STR00017##
Step A: 3-Nitrobenzoate (35.3 g, 195 mmol) in triflic acid (100 mL)
at 0.degree. C. was added NIS (43.8 g, 195 mmol) in ten portions.
Remove ice bath and stir for 48 hrs. The reaction typically goes to
50% completion. At this time more NIS could be added or cool to
0.degree. C. and quench with careful dropwise addition of water.
The mixture was extracted three times with EtOAc (250 mL) and the
combined extracts were washed with a 10% NaHSO.sub.3 solution,
followed by water. The organics were dried over Na.sub.2SO.sub.4,
concentrated, and purified on silica gel (10% EtOAc in Hex)
affording 24.1 g.
Step B: Tin chloride (88.6 g, 392 mmol) in EtOH (50 mL) was
refluxed and the nitrobenzoate from step A (24.1 g, 78.4 mmol) in
1:1 THF:EtOH (100 mL) was added dropwise. The reaction mixture was
refluxed for 30 minutes then cooled to 0.degree. C. The resulting
solution was basified to pH 8-9 with aq. Na.sub.2CO.sub.3. The
aqueous layer was extracted three times with EtOAc (700 mL) and the
combined extracts were washed with saturated NaHCO.sub.3 then
brine. The organics were dried over Na.sub.2SO.sub.4 and
concentrated to afford 21.7 g of the crude aniline which was used
without further purification.
Step C: To a 0.degree. C. solution of aniline from step B (21.7 g,
78.3 mmol) in 3:1 CH.sub.2Cl.sub.2:pyridine (75 mL) was added
methanesulfonyl chloride (6.36 mL, 82.2 mmol). The ice bath was
removed after 15 minutes and the solution was stirred overnight at
room temperature. The reaction mixture was extracted several times
with 1N HCl. The organic phase was dried, concentrated, and
chromatographed (1:1 EtOAc:Hex) to afford 25.2 g of the desired
sulfonamide as a white solid.
Step D: The sulfonamide from step C (23.6 g, 66.5 mmol) in DMF (75
mL) at 0.degree. C. was treated with 60% NaH (2.92 g, 73.1 mmol).
The solution stirred for 30 minutes before MeI (4.55 mL, 73.1 mmol)
was added. The ice bath was removed and the solution was stirred at
rt for twelve hours. The reaction was quenched with saturated
NH.sub.4Cl solution and extracted three times with EtOAc (150 mL).
The combined organic were washed with water (5.times.50 mL), dried,
concentrated to afford 25.3 g of the desired methylated anilide
which was used without further purification.
Step E: Trans-2-methylcyclopropanemethanol (7.0 g, 81 mmol) was
added to a solution of PCC (28 g, 130 mmol) in CH.sub.2Cl.sub.2
(225 mL). The solution became black and was stirred for three hours
at room temperature. The reaction mixture was diluted with ether
(250 mL) and decanted. The liquid solution was filtered through a 4
inch plug of Florisil and the solvent was removed by distillation
through a Vigreux column to afford 10 g of the desired
aldehyde.
Step F: To a solution of PPh.sub.3 (12.4 g, 47.5 mmol) in
CH.sub.2Cl.sub.2 (100 mL) at 0.degree. C. was added CBr.sub.4 (7.88
g, 23.7 mmol). The reaction mixture was stirred for 10 minutes then
treated with the carboxaldehyde from step E (1.0 g, 12 mmol). The
solution was stirred for 30 minutes at 0.degree. C. then 1 hr at
room temperature. Hexane was added and the solids were filtered,
and the filtrate was concentrated to afford 4.4 g of the
dibromide.
Step G: The dibromide from step F (15.4 g, 64.1 mmol) in 60 mL of
cyclohexane at -78.degree. C. was treated with 2.0 M n-BuLi in
cyclohexane (64.1 mL, 128 mmol). The resulting reaction mixture was
stirred at -78.degree. C. for 1 hr then warmed to room temperature
where it was stirred for 2 hr. The reaction was quenched with water
and extract with cyclohexane (3.times.25 mL). The product was
purified by distillation (bp=69-72 C).
Step H: A 100 mL 3-neck round bottom flask was charged with
InCl.sub.3 (0.829 g, 10.4 mmol) and dried under vacuum with a heat
gun for 2 minutes. THF (16 mL) was added under nitrogen and the
flask was immersed in a -78.degree. C. ice bath. DIBAL-H (12.4 mL,
1M in hexanes) was then added dropwise and the resulting solution
was stirred for 30 minutes at -78.degree. C. After this time, the
acetylene from step G (10.4 mmol) was added followed by 1.0 M
Et.sub.3B (1.6 mL, 1M in hexanes). This reaction mixture was
stirred at -78.degree. C. for 2.5 hr then warmed to room
temperature. DMI (12 mL) and aryliodide from step D (1.47 g, 4.0
mmol) was added followed by a palladium trifurylphosphine complex
[prepared from Pd.sub.2(DBA).sub.3.degree. CHCl.sub.3 (20 mg) and
trifurylphosphine (28 mg) in THF (6 mL)]. The resulting reaction
mixture was heated at 60.degree. C. for 2 hr, quenched with water
and extracted with ether (3.times.50 mL). The combined organic
extracts were dried, and concentrated and the product was purified
on a chiral OJ column (60:40 Hexane w/0.1% TFA:EtOH). Collection of
the first peak afforded 276 mg of the desired diastereomer.
Step I: To 276 mg (0.853 mmol) of the ester from step H in 10 mL
THF:MeOH:water (3:1:1) was added 2 N NaOH (0.64 mL, 1.28 mmol). The
solution was stirred at rt for 2 h. The reaction mixture was
concentrated and acidified with 2 N HCl (10 mL) and extracted with
CHCl.sub.3 (3.times.20 mL). The combined organic extracts were
dried over MgSO.sub.4, filtered, and concentrated to yield 253 mg
of the desired carboxylic acid. LCMS (M+H)=310.12
Step J: A solution containing 8.0 mg (0.026 mmol) of the carboxylic
acid from step I, 10.6 mg (0.031 mmol) of intermediate diamine IV,
11.4 mg (0.026 mmol) of BOP reagent and 0.026 mL (0.11 mmol) of
Hunig's base was stirred at rt for 1 h in 3 mL of DCM. The solvent
was evaporated and the residue was purified by reverse phase
chromatography to afford 17.6 mg of the title compound as a white
solid. 1H NMR (400 MHz, CDCl.sub.3) .delta. 7.95 (bd, H), 7.62-7.57
(m, 3H), 7.33-7.22 (m, 4H), 6.74 (s, 1H), 6.21 (d, 1H), 5.15 (dt,
1H), 4.66 (m, 1H), 3.96 (bd, 1H), 3.48-3.39 (m, 4H), 3.09-2.95 (m,
5H), 2.86 (s, 1H), 1.56-1.44 (m, 5H), 1. (m, 2H), 1.12-1.11 (d,
3H), 0.92-0.84 (m, 7H), 0.66-0.62 (m, 2H). LCMS (M+H)=569.2
The following compounds were prepared in a manner similar to the
title compounds of the foregoing examples using appropriate
starting materials and reagents.
TABLE-US-00001 Ex Structure 4 ##STR00018## 5 ##STR00019## 6
##STR00020## 7 ##STR00021## 8 ##STR00022## 9 ##STR00023## 10
##STR00024## 11 ##STR00025## 12 ##STR00026## 13 ##STR00027## 14
##STR00028## 15 ##STR00029## 16 ##STR00030## 17 ##STR00031## 18
##STR00032## 19 ##STR00033## 20 ##STR00034## 21 ##STR00035## 22
##STR00036## 23 ##STR00037## 24 ##STR00038## 25 ##STR00039## 26
##STR00040## 27 ##STR00041## 28 ##STR00042## 29 ##STR00043## 30
##STR00044## 31 ##STR00045## 32 ##STR00046## 33 ##STR00047## 34
##STR00048## 35 ##STR00049## 36 ##STR00050## 37 ##STR00051## 38
##STR00052## 39 ##STR00053## 40 ##STR00054## 41 ##STR00055## 42
##STR00056## 43 ##STR00057## 44 ##STR00058## 45 ##STR00059## 46
##STR00060## 47 ##STR00061## 48 ##STR00062## 49 ##STR00063##
While the invention has been described and illustrated with
reference to certain particular embodiments thereof, those skilled
in the art will appreciate that various adaptations, changes,
modifications, substitutions, deletions, or additions of procedures
and protocols may be made without departing from the spirit and
scope of the invention. It is intended, therefore, that the
invention be defined by the scope of the claims that follow and
that such claims be interpreted as broadly as is reasonable.
* * * * *